A technician is working the night shift and receives a CSF specimen on an infant. The technician makes a Gram stain of the spinal fluid, then reads the smear under the microscope. The report the technician sends to the physician reads as follows: "gram-negative bacillus, small and pleomorphic." What bacteria are being implied as the infecting agent?

Question

Quizplus · Accepted Answer

The description of the bacteria as gram-negative, small, and pleomorphic suggests Haemophilus influenzae, which is a common cause of bacterial meningitis in infants. E. coli is also a common cause of meningitis in infants and can also appear as small and pleomorphic, but it is most commonly described as a gram-negative rod. Legionella pneumophila is a gram-negative bacillus, but it does not typically cause meningitis. Staphylococcus aureus is a gram-positive cocci and is not a common cause of meningitis.

A Technician Is Working the Night Shift and Receives a CSF